Western civilisation has hitherto depended for its survival on two great families of nations: the Europeans and the North Americans. Today, however, with both the European Union and the United States inhibited by timidity, a power vacuum has emerged across oceans and continents where once the Pax Britannica, and later the Pax Americana, preserved the rule of law.

This vacuum is becoming more dangerous by the day. Not only are piracy and slavery, two evils abolished by the Royal Navy, making a return; even more sinister has been the emergence of gunboat diplomacy in the Middle East. Iranian warships pass through the Suez Canal with the blessing of the new Egyptian regime, while Turkey — a member of Nato — threatens to deploy its navy against Israel. Diplomacy counts for little when the Israeli embassy in Cairo can be stormed with impunity by an Islamist lynch mob, while Mubarak's successor Field Marshal Tantawi failed to take a call from Netanyahu and took hours before responding to Leon Panetta, the US Defense Secretary. The degradation of diplomacy is demonstrated by the fact that the UN can host the Durban III "anti-racism" conference whose sole purpose is to pillory "racist" Israel, while the General Assembly recognises the unilateral declaration of statehood by the Palestinian Authority. In reality, the Jewish state grants equal rights to Arabs, while the leaders of the putative Palestinian state have stipulated the ethnic cleansing of Jews. The West may turn a blind eye to Israel's isolation, but it is a portent of our own.

Meanwhile Russia and China ruthlessly extend their spheres of influence, seemingly without resistance from Western powers. North Korea continues to export lethal technologies all over the globe, while other rogue states, from the Venezuela of Hugo Chávez to the Belarus of Lukashenko or the Syria of Bashar al-Assad, thumb their noses at the West. In the absence of American leadership, international order swiftly reverts to anarchy. "Speak softly and carry a big stick" was a "homely old adage" even when Teddy Roosevelt quoted it a century ago. In the Obama era we have a revised version. The President speaks incessantly to his chosen constituency, but his stick is, well, not very big. At a time when China is building an ocean-going navy, the US Navy is shrinking to levels we have not seen since Pearl Harbor.

The decline of American sea power may not frighten tyrants, but it should certainly frighten Europe. Apart from France and Britain, Europe has all but disarmed itself, and even these two once-great powers struggled to topple a Gaddafi. Indeed, without US military technology, Libya might not have been liberated. Europe is in no position to take over the role vacated by Obama. The state of nature abhors a vacuum, and if the democracies don't fill it, the dictators will. Europeans claim to believe in soft power, but they are the first to call in the US cavalry as soon as the question of deposing despots or taking on Islamist terrorists arises.